1 files changed, 45 insertions, 15 deletions

diff --git a/kernel/audit.c b/kernel/audit.c
index 09a37581213b..644ab825118b 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -106,6 +106,7 @@ static LIST_HEAD(audit_freelist);
 static struct sk_buff_head audit_skb_queue;
 static struct task_struct *kauditd_task;
 static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait);
+static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait);
 
 /* The netlink socket is only to be read by 1 CPU, which lets us assume
  * that list additions and deletions never happen simultaneously in
@@ -130,6 +131,7 @@ struct audit_buffer {
         struct list_head     list;
         struct sk_buff       *skb;      /* formatted skb ready to send */
         struct audit_context *ctx;      /* NULL or associated context */
+        int                  gfp_mask;
 };
 
 static void audit_set_pid(struct audit_buffer *ab, pid_t pid)
@@ -226,7 +228,7 @@ static int audit_set_rate_limit(int limit, uid_t loginuid)
 {
         int old          = audit_rate_limit;
         audit_rate_limit = limit;
-        audit_log(NULL, AUDIT_CONFIG_CHANGE, 
+        audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, 
                         "audit_rate_limit=%d old=%d by auid=%u",
                         audit_rate_limit, old, loginuid);
         return old;
@@ -236,7 +238,7 @@ static int audit_set_backlog_limit(int limit, uid_t loginuid)
 {
         int old          = audit_backlog_limit;
         audit_backlog_limit = limit;
-        audit_log(NULL, AUDIT_CONFIG_CHANGE,
+        audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
                         "audit_backlog_limit=%d old=%d by auid=%u",
                         audit_backlog_limit, old, loginuid);
         return old;
@@ -248,7 +250,7 @@ static int audit_set_enabled(int state, uid_t loginuid)
         if (state != 0 && state != 1)
                 return -EINVAL;
         audit_enabled = state;
-        audit_log(NULL, AUDIT_CONFIG_CHANGE,
+        audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
                         "audit_enabled=%d old=%d by auid=%u",
                         audit_enabled, old, loginuid);
         return old;
@@ -262,7 +264,7 @@ static int audit_set_failure(int state, uid_t loginuid)
             && state != AUDIT_FAIL_PANIC)
                 return -EINVAL;
         audit_failure = state;
-        audit_log(NULL, AUDIT_CONFIG_CHANGE,
+        audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
                         "audit_failure=%d old=%d by auid=%u",
                         audit_failure, old, loginuid);
         return old;
@@ -274,6 +276,7 @@ int kauditd_thread(void *dummy)
 
         while (1) {
                 skb = skb_dequeue(&audit_skb_queue);
+                wake_up(&audit_backlog_wait);
                 if (skb) {
                         if (audit_pid) {
                                 int err = netlink_unicast(audit_sock, skb, audit_pid, 0);
@@ -417,7 +420,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
                 if (status_get->mask & AUDIT_STATUS_PID) {
                         int old   = audit_pid;
                         audit_pid = status_get->pid;
-                        audit_log(NULL, AUDIT_CONFIG_CHANGE,
+                        audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
                                 "audit_pid=%d old=%d by auid=%u",
                                   audit_pid, old, loginuid);
                 }
@@ -435,7 +438,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
                 err = audit_filter_user(pid, msg_type);
                 if (err == 1) {
                         err = 0;
-                        ab = audit_log_start(NULL, msg_type);
+                        ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
                         if (ab) {
                                 audit_log_format(ab,
                                                  "user pid=%d uid=%u auid=%u msg='%.1024s'",
@@ -522,7 +525,7 @@ static int __init audit_init(void)
         skb_queue_head_init(&audit_skb_queue);
         audit_initialized = 1;
         audit_enabled = audit_default;
-        audit_log(NULL, AUDIT_KERNEL, "initialized");
+        audit_log(NULL, GFP_KERNEL, AUDIT_KERNEL, "initialized");
         return 0;
 }
 __initcall(audit_init);
@@ -586,6 +589,7 @@ static struct audit_buffer * audit_buffer_alloc(struct audit_context *ctx,
                 goto err;
 
         ab->ctx = ctx;
+        ab->gfp_mask = gfp_mask;
         nlh = (struct nlmsghdr *)skb_put(ab->skb, NLMSG_SPACE(0));
         nlh->nlmsg_type = type;
         nlh->nlmsg_flags = 0;
@@ -644,17 +648,42 @@ static inline void audit_get_stamp(struct audit_context *ctx,
  * syscall, then the syscall is marked as auditable and an audit record
  * will be written at syscall exit.  If there is no associated task, tsk
  * should be NULL. */
-struct audit_buffer *audit_log_start(struct audit_context *ctx, int type)
+
+struct audit_buffer *audit_log_start(struct audit_context *ctx, int gfp_mask,
+                                     int type)
 {
         struct audit_buffer     *ab     = NULL;
         struct timespec         t;
         unsigned int            serial;
+        int reserve;
 
         if (!audit_initialized)
                 return NULL;
 
-        if (audit_backlog_limit
-            && skb_queue_len(&audit_skb_queue) > audit_backlog_limit) {
+        if (gfp_mask & __GFP_WAIT)
+                reserve = 0;
+        else
+                reserve = 5; /* Allow atomic callers to go up to five 
+                                entries over the normal backlog limit */
+
+        while (audit_backlog_limit
+               && skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) {
+                if (gfp_mask & __GFP_WAIT) {
+                        int ret = 1;
+                        /* Wait for auditd to drain the queue a little */
+                        DECLARE_WAITQUEUE(wait, current);
+                        set_current_state(TASK_INTERRUPTIBLE);
+                        add_wait_queue(&audit_backlog_wait, &wait);
+
+                        if (audit_backlog_limit &&
+                            skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
+                                ret = schedule_timeout(HZ * 60);
+
+                        __set_current_state(TASK_RUNNING);
+                        remove_wait_queue(&audit_backlog_wait, &wait);
+                        if (ret)
+                                continue;
+                }
                 if (audit_rate_check())
                         printk(KERN_WARNING
                                "audit: audit_backlog=%d > "
@@ -665,7 +694,7 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, int type)
                 return NULL;
         }
 
-        ab = audit_buffer_alloc(ctx, GFP_ATOMIC, type);
+        ab = audit_buffer_alloc(ctx, gfp_mask, type);
         if (!ab) {
                 audit_log_lost("out of memory in audit_log_start");
                 return NULL;
@@ -689,7 +718,7 @@ static inline int audit_expand(struct audit_buffer *ab, int extra)
 {
         struct sk_buff *skb = ab->skb;
         int ret = pskb_expand_head(skb, skb_headroom(skb), extra,
-                                   GFP_ATOMIC);
+                                   ab->gfp_mask);
         if (ret < 0) {
                 audit_log_lost("out of memory in audit_expand");
                 return 0;
@@ -808,7 +837,7 @@ void audit_log_d_path(struct audit_buffer *ab, const char *prefix,
                 audit_log_format(ab, " %s", prefix);
 
         /* We will allow 11 spaces for ' (deleted)' to be appended */
-        path = kmalloc(PATH_MAX+11, GFP_KERNEL);
+        path = kmalloc(PATH_MAX+11, ab->gfp_mask);
         if (!path) {
                 audit_log_format(ab, "<no memory>");
                 return;
@@ -849,12 +878,13 @@ void audit_log_end(struct audit_buffer *ab)
 /* Log an audit record.  This is a convenience function that calls
  * audit_log_start, audit_log_vformat, and audit_log_end.  It may be
  * called in any context. */
-void audit_log(struct audit_context *ctx, int type, const char *fmt, ...)
+void audit_log(struct audit_context *ctx, int gfp_mask, int type, 
+               const char *fmt, ...)
 {
         struct audit_buffer *ab;
         va_list args;
 
-        ab = audit_log_start(ctx, type);
+        ab = audit_log_start(ctx, gfp_mask, type);
         if (ab) {
                 va_start(args, fmt);
                 audit_log_vformat(ab, fmt, args);